Water Tank Cleaning & Disinfection



We are committed to providing our customers with an exceptional level of customer service. Over 90% of our first-time clients return to us for water tank cleaning. They know that we only work with effective equipment, guarantee competitive prices, and focus on health and safety.

Over time, it's normal for sediment to build up on water tank bottoms and for staining to develop on water tank internals. You may also see biofilm on the sides of the water tank or on top of the water. All of these provide the nutrients required for various bacteria, including Legionella, to thrive within your water system and must be removed to maintain system integrity through professional water tank cleaning and testing every twelve months for both hot water tanks and cold water tanks, although 6 months is recommended for any storage of potable water.

HSG274 part 2 states that cold water tanks should be inspected annually with remedial works completed as required, based on the water tank testing inspection carried out. These remedial works may include water tank cleaning and disinfection to remove contamination and maintain high-quality water for your customers and you.



Image of a water tank before cleaning



Image of a water tank after cleaning



At pHX Water, we take the hassle away from water maintenance. You can depend on us for all the cleaning, sampling, and reporting services you need to meet water maintenance regulations and provide safe drinking water.

We can protect your customers, clients, and employees from harmful bacteria.

Legionella is a naturally occurring form of bacteria found in water sources such as rivers, lochs, ponds, and reservoirs. When water is pumped into your hot water tank or cold storage tank, legionella has a new breeding ground. If not properly managed, the non-hazardous amounts of legionella can rapidly multiply and pose a threat to health.

Legionella enters the body through the respiratory system via droplets of water. Even a small amount of legionella causes a 10% mortality rate.

Water systems are an often overlooked yet essential part of any commercial or industrial building. Without a water tank, your building would not be able to serve its purpose. It is important to regularly check the levels of bacteria in your water tank.

Our water tank cleaning services identify and eliminate harmful levels of bacteria, biofilm, and debris in your tank.

  • Using only approved chemical products
  • Applying adequate chemicals that remove biofilms and staining
  • Fully trained confined space entry staff and adequate procedures
  • A full report detailing water tank conditions, defects and cleanliness
  • Digital image survey
  • Certificate of disinfection

We have suitable safe working procedures including method statements, risk assessments and COSHH data sheets that we will supply on any water tank cleaning service. These will be sent to you prior to work commencing and our engineers will have a copy on the day. We have all relevant safety equipment and training for working in confined spaces, including the use of breathing apparatus if required for use in commercial or domestic water tanks. We will always have a first aider as part of our team.

Our reports include details on the conditions of the water tank and recommendations to improve water quality. Common causes for concern are corrosion on galvanised water tanks as this can provide a habitat for bacteria and can also eventually lead to the corroded area breaching and flooding the property with significant damage caused. We may also highlight poor system design or poor plumbing practice which is causing stagnation or poor throughflow in your system. Bacteria love stagnant water and it’s essential that this poor practice be highlighted so a remedial action plan can be implemented to reduce the likelihood of bacterial issues within your water system.

We are highly experienced at cleaning and disinfection of drinking water systems and use only high-quality products effective at removing all contaminants including biofilm, mould, algae, fungus and Iron staining (orange tinge that you see in cold water tanks and on plumbing fittings). A common practice in water tank cleaning is to use chlorine which is proven ineffective against biofilm and certain types of bacteria such as Cryptosporidium. Chlorine essentially disinfects the outer layer only and doesn’t remove the problem, only masking it for a short period, which is why we only ever use high-quality products when cleaning your water tanks.

One Simple Package

At pHX, we are committed to making water maintenance as easy as possible. Water tank issues always arise at the most unexpected times, which means that finding a lump sum can be difficult. This is true for the majority of our clients who pay for their day-to-day services and equipment on a monthly basis.

People in Scotland call us when they have a water maintenance crisis. We offer excellent customer service, transparent prices, and a comprehensive monthly package. Our one simple package includes all of the services you need to assess, control, and manage your water system in one monthly payment.

We know that not every organisation is the same. When you contact our team, we can highlight the sort of services that similar businesses procure from us. Here are some of the services that our clients choose for their monthly package:

Extra water samples

  • Water tank disinfection
  • Water treatment plant maintenance
  • Pipework cleaning and disinfection
  • Confined space entry
  • Cold and hot water tank cleaner services

Whichever services you choose will benefit from our years of experience in the industry and specialist equipment. With our one simple package structure, you can tailor each package to suit your needs.

For a list of all services, visit our How We Work page.



Water tank sampling is an essential part of any effective Legionella Control Scheme as it measures the effectiveness of the control measures that had previously been put in place. While water tank sampling is not always necessary as the water supplied to a building should be fit to drink. Where there is a potential for microorganisms to grow in areas of hot and cold water tanks, water tank sampling should be carried out in the following circumstances:

  • Water tanks where drinking water is stored
  • Water tanks where the systems are treated with biocide and storage and distribution temperatures are lowered
  • Where control measures cannot be consistently kept regulated
  • Where potential hazards or contaminants have been identified
  • Following or during a Legionellosis outbreak
  • Where the inhabitants of a building are deemed vulnerable
  • If a Legionella Risk Assessment recommends water tank sampling and advise it will aid in monitoring.

It is important to note Legionella bacteria can multiply at temperatures between 20°C and 45°C. One of the best ways to control the risks of legionella bacteria in your water tanks is to ensure that the temperature in your cold water tanks is kept below 20°C and the hot water tanks is kept above 50°C.

Why not add some water samples to confirm that the cleaning procedure was effective



Over the course of months and years, your water tank will develop stains and sediment will build-up. If your private water supply covers large industrial or commercial buildings, this build-up can occur even sooner. Sometimes, a biofilm can appear on the internal surface of the tank itself or even on top of the water.

Coldwater tanks are more at risk of developing large amounts of legionella. Despite this, it is important to book a tank cleaning appointment every twelve months for both hot and cold water tanks.

We recommend that large industrial and commercial building managers book a tank cleaning call once every six months.

Our water tank disinfection team conduct a comprehensive service. When you choose pHX Water, you can rest assured that we will leave no stone unturned. We have worked in the water maintenance industry for years, and understand how different factors can impact the quality of your water.


What Water Tank Cleaning Services Do You Offer?

Most of our clients come to us for water tank cleaning and reports. We recommend booking a water tank cleaning appointment every six to twelve months. Doing so can ensure that the water in your system is safe for consumption.

Our cold and hot water tank cleaners provide detailed information about:

  • Poor system designs
  • Poor plumbing practices
  • Causes for concern (such as corrosion)
  • Ways to improve water quality
  • Concerning findings

Our tank water services would be incomplete without premium-quality equipment. We only use industry-approved chemical products for our clients. When you choose pHX Water, you can rest assured that you will receive the best tank cleaning practices that the industry has to offer.

Once our team have surveyed and cleaned your water system, we will present you with a tank cleaning certificate. These certificates are essential for industrial and commercial building owners who need to comply with water regulation laws.

Landlords who use a private water supply also have to regularly clean and check their water supply.


How Frequently Should I Book PHX Tank Cleaning Services?

When it comes to building maintenance, water tank cleaning can often be pushed to the bottom of the list. Although it is tempting to leave your tank maintenance to the last minute, harmful levels of bacteria can proliferate through your system if left unchecked.

Once your system is infected with a large amount of debris, bacteria, or biofilm, the quality of your water will rapidly decrease. In some cases, your clients, customers, and employees can become ill from drinking poor-quality water.

It is important to clean your tank once a year to ensure your water is safe for human consumption. Failure to do so can lead to fines. Your business or organisation can even be shut down by the water maintenance governing body.

We recommend bi-annual water tank cleaning check-ups for industrial and commercial buildings that are supplying water to a large number of people.

If any of the following situations arise, contact our tank water services team immediately.

  • A water inspection has found a large amount of legionella in your system
  • Your water tank has been altered or entered for maintenance purposes, which could lead to contamination
  • There has been an outbreak or even a suspected outbreak of legionella


What is potable water?

Potable water is any drinking water that is a particularly high risk for legionellosis as it is being consumed, perhaps also by vulnerable people which can be fatal. This is why it is essential that you have a professional water tank cleaning, testing and sampling carried out to ensure your water tanks are not contaminated.


What is legionella?

Legionella is a form of bacterium that is found naturally in freshwater environments such as your local lochs and rivers. Legionella can become a risk when it grows and spreads to man-made water systems such as your showers or drinking water.


What is COSHH?

COSHH stands for 'Control of Substances Hazardous to Health'. COSHH is a set of regulations put in place to protect workers from ill health when working with specific substances and materials. This means that you can ensure when carrying out your water tank cleaning our workers are competent and professional when using any chemicals and are qualified to do so.


Why don't you use chlorine when cleaning my water tanks?

Chlorine has been proven ineffective against biofilm and certain types of bacteria such as Cryptosporidium. Chlorine essentially disinfects the outer layer only and doesn’t remove the problem, only masking it for a short period, which is why we only ever use high-quality effective products when cleaning your water tanks.


What's the safest temperature for my water tanks?

Legionella bacteria can multiply at temperatures between 20°C and 45°C. One of the best ways to control the risks of legionella bacteria in your water tanks is to ensure that the temperature in your cold water tanks is kept below 20°C and the hot water tanks are kept above 50°C.



Water tank disinfection is just as important as cleaning the tanks. Bacteria that develop in the water tank will spread throughout the system and potentially multiply. Areas of the system where this is most likely to happen is a recirculating hot water system, low flow areas or dead legs within systems. A suitable and sufficient Legionella risk assessment will have highlighted all of these concerns and gave recommendations on how these can be improved.


Contact pHX Water

With rules and regulations constantly changing, it is important to speak to the experts. Our team have been working on commercial, industrial, and residential hot and cold water tanks for years. People all over Scotland trust us to stay up-to-date on the latest news, certificates, and laws. When you choose pHX Water, you can rest assured you are in safe hands.

To book a legionella risk assessment, or to make general inquiries, call us on 01738 472149. If you need to speak to someone in an emergency outside of normal working hours, call 07503 343328.




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